#define _CRT_SECURE_NO_WARNINGS 1
#include <stdio.h>

int main() {
    long n = 0;
    scanf("%ld", &n);
    long k = 1;
    int x = 1;
    while (n != 0)
    {
        int t = n % 10;
        if (t % 2 == 1)
        {
            k = k + x * 10 ;
        }
        n = n / 10;
        x = x * 10;
    }
    printf("%ld", k / 10);
    return 0;
}
